Answer:
The concentration is [-1 + sqrt(1+0.11t)]/0.1542 M
Explanation:
Let the concentration of CH3CHO after selected reaction times be y
Rate = Ky^2 = change in concentration of CH3CHO/time
K = 0.0771 M^-1 s^-1
Change in concentration of CH3CHO = 0.358 - y
0.0771y^2 = 0.358-y/t
0.0771ty^2 = 0.358 - y
0.0771ty^2 + y - 0.358 = 0
The value of y must be positive and is obtained in terms of t using the quadratic formula
y = [-1 + sqrt(1^2 -4(0.0771t)(-0.358)]/2(0.0771) = [-1 + sqrt(1+0.11t)]/0.1542 M
Answer: 406 hours
Explanation:

where Q= quantity of electricity in coloumbs
I = current in amperes = 39.5 A
t= time in seconds = ?
The deposition of copper at cathode is represented by:

Coloumb of electricity deposits 1 mole of copper
i.e. 63.5 g of copper is deposited by = 193000 Coloumb
Thus 19.0 kg or 19000 g of copper is deposited by =
Coloumb

(1hour=3600s)
Thus it will take 406 hours to plate 19.0 kg of copper onto the cathode if the current passed through the cell is held constant at 39.5 A
Answer:
Each gas have same number of molecules.
Explanation:
According to Avogadro law,
Equal volume of all the gases at same temperature and pressure have equal number of molecules.
Mathematical expression:
V ∝ n
V = Kn
V/n = K
k = constant
V = volume of gas
n = number of moles of gas
when volume change is changed from v1 to v2 and number of moles from n1 to n2 this law can be written as,
V1 / n1 = V2 /n2
This state that by increasing the number of moles of gas volume also goes to increase.